[case_222]

As I posted before I am rebuilding a K301. the head was black with an excessive amount of carbon. I doubt it was ever cleaned. I tried to scrape it with a plastic scraper, didn't do much maybe removing 5% of the carbon. Then I used some hard wood (poplar) and it did even worse than the plastic. So much for following the directions. Then I tried a brass detail brush, I have no doubt that it would have removed all the carbon but it was also scratching the head so I stopped using it. I assume that more scratches and a rough surface would only give the carbon more to adhere to. Then I tried a piece of green scotch brite, it was even more aggressive than the brass brush and I was concerned about the corners around the valve area so i stopped with that. I then turned to solvents, paint thinner, acetone, carb cleaner....none of them did anythingThen came the purple power......The stuff is like magic. I plugged the spark plug hole with some plastic and poured some purple power in the head. I let it sit a few hours and when I went to check back in on it it turned from purple to black. A quick rubbing with my bare finger and dumped it out to reveal 90% of the remaining carbon was gone. I am currently resoaking it to get the last bit off, I cant believe how easy it is to do compared to the hour I spent with the plastic and wood scrappers that are suggested in the Kohler manual.

 

[mastifflawyer]

Thanks for the tip. I use oven cleaner and it works about the same. I hate the smell though, so I will try the purple power next time. We plan to have an article about the topic in either the Tech Section or the Faqs. I always polish the head while I have it off. Also it is important to check to see if the head is warped. All of those topics shall be covered. Thanks again for the tip.

 

[Mjoe7]

What is the benefit of polishing the head on this design since it does'nt flow an air fuel mixture through it?
Thanks;
Mike

 

[Hydriv]

What is the benefit of polishing the head on this design since it doesn't flow any air/fuel mixture through it?
Thanks;
Mike

The purpose behind polishing the head is to have a surface so smooth that it is difficult for carbon to stick to it.

Jack says that it's easier to do the polishing than to spray PAM into the carb every ten minutes while using the tractor. :sidelaugh: :sidelaugh: :sidelaugh:

 

[mastifflawyer]

Yes-As Tom said I believe that the carbon does not attach as easily. I have pulled heads that I have polished after some use and they seem to be pretty clean. Scientifically, that is no proof of the effectiveness because there are so many variables. Gas blends today create less carbon buildup. I use Seafoam often. And other than my 648, nothing gets worked too hard. So does it work? I don't know, but I feel better about it, and I do love polishing things.

 

[case_222]

I didn't notice any yellowing at all, maybe its because it is covered in PP and no air is getting at it....I don't know. I really am not concerned about it, like you said it not visible and i planned on polishing the head and having it shaved a little too.

I am a believer in SEAFOAM to prevent carbon build up but I don't think it does much to get rid of it. When I first got the tractor I pulled the plug rotated until TDC and filled with Seafoam to sit for several days. when I started there was a ton of smoke. I think it was the seafoam burning off more than the carbon burning off. By the look of my head once I pulled it I don't see where anymore carbon would have fit with out having lifter issues.

On my yamaha outboard it seafoam deep creep worked wonders. It was sputtering a bit, I sprayed deep creep into the vacuum lines and ones the lines were clear it ran smooth with improved holeshot.

 

[mikebramel]

That seafoam works best when you work the engine and get it real hot then put it in till it almost chokes out and let it sit overnight

 

[horton20]

Hi from horton20

I found that sandblasting works for me.Sandblast the whole head works good.